CHICAGO - A migraine pill seems to help alcoholics taper off their drinking without detox treatment, researchers report, offering a potential option for a hard-to-treat problem.
The drug, Topamax, works in a different way than three other medications already approved for treating alcoholism.
Experts said the drug is likely to appeal to heavy drinkers who would rather seek help from their own doctors, rather than enter a rehab clinic to dry out. The drug costs at least US$350 a month.
But side effects are a problem, and it's unclear whether the findings will make a dent in an addiction that affects millions of North Americans.
Addiction specialists not involved in the study said the findings are promising, although side effects such as trouble concentrating, tingling and itching caused about one in five people to drop out of the study. Drowsiness and dizziness are also problems.
"The size of the treatment effect is larger than in most of the other medications we've seen," said Dr. Mark Willenbring of the National Institute on Alcohol Abuse and Alcoholism. "And all the drinking variables changed in the right direction."
The study, published in Wednesday's Journal of the American Medical Association, was funded by the maker of the drug, Johnson & Johnson Inc.'s Ortho-McNeil Neurologics. The researchers also reported financial ties to the company. Ortho-McNeil reviewed the manuscript, but did not change the results or interpretation, the researchers reported.
The study followed 371 heavy drinkers for 14 weeks. About half were randomly assigned to take Topamax, also called topiramate, in gradually increasing doses. The others took dummy pills.
All volunteers were encouraged -- but not required -- to stop drinking.
At the start of the study, they drank, on average, 11 standard drinks daily. That's about two six-packs of beer each day, or two bottles of wine, or a pint of hard liquor.
By the end of the study, 27 of the 183 people, or 15 per cent, who took Topamax had quit drinking entirely for seven weeks or more. That compared to six out of 188, or three per cent, in the placebo group.
Others cut back. The Topamax group cut back to six drinks a day, on average, assuming everyone who dropped out of the study relapsed into heavy drinking. That compared to seven drinks a day for the placebo group.
"You can come in drinking a bottle of scotch a day and get treatment without detox," said Dr. Bankole Johnson of the University of Virginia, who led the study, which was conducted at 17 U.S. sites from 2004-2006.
The study didn't follow the drinkers long-term, so it's unclear how many relapsed after they stopped taking the pill.
But there were lasting effects for Tom Wolfe, 44, a carpenter from Earlysville, Va., who said he has been sober for two years thanks to Topamax. After years of heavy drinking, he took part in an earlier Topamax study. He felt "a little lightheaded" at first until he got used to the drug. Alcohol lost its enjoyment, strengthening his resolve to quit.
"It's been a miracle to me," Wolfe said. "It got the monkey off my back."
The drug works by inhibiting dopamine, the brain's "feel-good" neurotransmitters that are involved in all addictions, said Stephen Dewey, a neuroscientist the Brookhaven National Laboratory, who was not involved in the study but does similar research.
It's a new approach, he said, that "clearly did work on a very small subset in the population."
Willenbring, who wrote an accompanying editorial, predicts that a future pill, although probably not Topamax, will do for alcohol dependence what Prozac did for depression: Remove the stigma.
Prozac changed the nature of depression treatment 20 years ago by allowing patients to see their family doctors for help, Willenbring said. An effective drug with few side effects could do the same for alcoholism treatment, he said.
"This is a huge market," Willenbring said. "We're approaching a Prozac moment."
But Topamax has big obstacles. With the drug maker's patent expiring next year, there won't be any big push to advertise it for alcoholism, Willenbring said.
Doctors are free to prescribe drugs for uses that have not been approved, but drug companies are prohibited by law from marketing drugs for these so-called "off-label" uses.
On Tuesday, Dr. Sidney Wolfe, director of Public Citizen's health research group, sent a protest letter to the U.S. Food and Drug Administration questioning the promotion of Topamax for alcoholics by researchers funded by Ortho-McNeil.
"This is a very bad message to send out," Wolfe said.
Ortho-McNeil has no plans to seek federal approval for the drug as an alcoholism treatment, said company spokeswoman Tricia Geoghegan. The company dropped development of new uses for the drug in 2004, but has continued to support some research.